May have to look around a bit --- does that upper section separate from the bottom ? That's an odd one -- if not.
Often the shades could be used w/ different mounts depending on application. The nicer ones with the neck had actual through screw sockets that can be quite expensive. Others used the tri screw mount w/ the socket in the mount.
I like to use vintage lighting in my projects as most are old building ..... shocking how much the really nice condition stuff sells for
